Update bootstrap script CLI options

I made them easier to update by simply pasting in the output from the
script. The snippet also included the exact command I used to extract
the command line options.
doc(bootstrap): avoid using URL

It's considered insecure. See
https://github.com/saltstack/salt/pull/11446#issuecomment-38364901.
doc(topic/bootstrap): document `-i` CLI option

It was added in https://github.com/saltstack/salt-bootstrap/pull/348.
Merge pull request #11456 from JensRantil/bootstrap-cli-minid-opt

Bootstrap script: Document new `-i` CLI option